JP6421196B2 - Target generating apparatus and filter structure manufacturing method - Google Patents

Description

  The present disclosure relates to a filter structure, a target generation device, and a method for manufacturing a filter structure.

  In recent years, along with miniaturization of semiconductor processes, miniaturization of transfer patterns in optical lithography of semiconductor processes has been rapidly progressing. In the next generation, fine processing of 60 nm to 45 nm, and further fine processing of 32 nm or less will be required. Therefore, for example, in order to meet the demand for fine processing of 32 nm or less, development of an exposure apparatus combining an apparatus for generating extreme ultraviolet (EUV) light with a wavelength of about 13 nm and a reduced projection reflection optical system is expected. .

  As the EUV light generation apparatus, an LPP (Laser Produced Plasma) type apparatus that uses plasma generated by irradiating a target material with laser light, and a DPP (Discharge Produced Plasma) that uses plasma generated by discharge. There have been proposed three types of devices: a device of the type and a device of SR (Synchrotron Radiation) type using orbital radiation.

Japanese Patent No. 4854024 JP 2013-140771 A Special table 2008-532228 gazette US Patent Application Publication No. 2004/0071266

Overview

  A filter structure (110, 110A, 110B, 120, 130, 150, 160) according to an aspect of the present disclosure includes a filter (111, 121, 121A, 121B, 131, 151) made of a porous material and the filter. Sockets (115, 126, 144, 156).

  A target generation device (26) according to another aspect of the present disclosure includes the above-described filter structure, and a flange (301) that houses the filter structure and includes a flow path that passes through the filter structure inside. A tank portion (260) that communicates with the flow path in the flange and stores a predetermined target material therein, and is provided in the flange, and the tank is provided via the flow path in the flange. A nozzle portion (266) communicating with the space in the portion.

  A manufacturing method of a filter structure according to still another aspect of the present disclosure is a manufacturing method of a filter structure including a filter made of a porous material, and the filters each partially formed with a masking material are arranged to overlap each other. Spraying a material (1008) having a thermal expansion coefficient substantially equal to that of the filter around the filter on which the masking material is formed; and processing the material to expose a part of the masking material And a step of removing the masking material.

Several embodiments of the present disclosure are described below by way of example only and with reference to the accompanying drawings.
FIG. 1 is a diagram schematically illustrating a configuration example of an exemplary LPP type EUV light generation system. FIG. 2 is a schematic diagram illustrating a schematic configuration example of a target generation device including the target supply unit illustrated in FIG. 1. FIG. 3 is a cross-sectional view illustrating a schematic configuration example of the filter unit. FIG. 4 is a cross-sectional view illustrating a schematic configuration example of the filter unit according to the first embodiment. FIG. 5 is a cross-sectional view illustrating a schematic configuration example of a filter laminate according to a first modification of the first embodiment. FIG. 6 is a cross-sectional view illustrating a schematic configuration example of a filter laminate according to a second modification of the first embodiment. FIG. 7 is a cross-sectional view illustrating a schematic configuration example of the filter unit according to the second embodiment. FIG. 8 is a perspective view showing a schematic configuration example of the filter structure shown in FIG. FIG. 9 is a view showing a cross-sectional structure when the filter laminate in the filter structure shown in FIG. 8 is cut in a plane perpendicular to the extending direction of the internal space. FIG. 10 is a diagram illustrating a cross-sectional shape when the filter laminate according to the first modification of the second embodiment is cut in a plane perpendicular to the extending direction of the internal space. FIG. 11 is a diagram illustrating a cross-sectional shape when the filter laminate according to the second modification of the second embodiment is cut in a plane perpendicular to the extending direction of the internal space. FIG. 12 is a cross-sectional view illustrating a schematic configuration example of the filter unit according to the third embodiment. FIG. 13 is a view showing a cross-sectional structure when the filter laminate in the filter section shown in FIG. 12 is cut in a plane perpendicular to the extending direction of the internal space. FIG. 14 is a cross-sectional view illustrating a schematic configuration example of a filter unit according to the fourth embodiment. FIG. 15 is a cross-sectional view illustrating a schematic configuration example of a filter unit according to the fifth embodiment. FIG. 16 is a cross-sectional view illustrating a schematic configuration example of the filter unit according to the sixth embodiment. FIG. 17 is a flowchart illustrating an example of a manufacturing process for manufacturing the filter structure according to the sixth embodiment by thermal spraying. FIG. 18 is a process cross-sectional view for explaining the process of the manufacturing process shown in FIG. 17 (1). FIG. 19 is a process cross-sectional view for explaining the manufacturing process shown in FIG. 17 (2). FIG. 20 is a process cross-sectional view for explaining the manufacturing process shown in FIG. 17 (3). FIG. 21 is a process cross-sectional view for explaining the manufacturing process shown in FIG. 17 (4). FIG. 22 is a process cross-sectional view for explaining the process of the manufacturing process shown in FIG. 17 (5). FIG. 23 is a process cross-sectional view for explaining the manufacturing step shown in FIG. 17 (6).

Embodiment

Contents 1. Outline 2. 2. Overview of Extreme Ultraviolet Light Generation Device 2.1 Configuration 2.2 Operation Explanation of Terms 3.1 Above 2. 3.2 Explanation of unique terms for each disclosure 4. Target generation device 4.1 Configuration 4.2 Operation 5. Filter section 5.1 Configuration 5.2 Operation 5.3 Problem 6. Embodiment 1
6.1 Configuration 6.2 Action 7. Modified Example of Embodiment 1 7.1 Configuration 7.1.1 First Modified Example 7.1.2 Second Modified Example 7.1.3 Other Modified Examples 7.2 Operation 8. Embodiment 2
8.1 Configuration 8.2 Action 9. Modification of Embodiment 2 9.1 Configuration 9.1.1 First Modification 9.1.2 Second Modification 9.2 Action 10. Embodiment 3
10.1 Configuration 10.2 Action 11. Embodiment 4
11.1 Configuration 11.2 Action 12. Embodiment 5
12.1 Configuration 12.2 Action 13. Embodiment 6
13.1 Configuration 13.2 Action 14. Constituent material 14.1 Socket cap material 14.2 Filter material 15. Manufacturing process of filter structure by thermal spraying

  Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. Embodiment described below shows some examples of this indication, and does not limit the contents of this indication. In addition, all the configurations and operations described in the embodiments are not necessarily essential as the configurations and operations of the present disclosure. In addition, the same referential mark is attached | subjected to the same component and the overlapping description is abbreviate | omitted.

1. SUMMARY Embodiments of the present disclosure relate to supply of a target material used for generation of EUV light, and more specifically, to a target generation apparatus that supplies a target material into a chamber for generating EUV light. It may be. In the supply of the target material, it is necessary to supply the target material accurately and stably to the region where the plasma emitting EUV light is generated. However, supply of the target material to the plasma generation region may become unstable due to particles or the like inherent in the target material. Therefore, in the following embodiments of the present disclosure, a target generation device capable of stably supplying a target material is illustrated. However, the present disclosure is not limited to these items, and may relate to all items related to the target material used for generating EUV light.

2. 2. General Description of EUV Light Generation System 2.1 Configuration FIG. 1 schematically shows a configuration of an exemplary LPP type EUV light generation system. The EUV light generation apparatus 1 may be used together with at least one laser apparatus 3. In the present application, a system including the EUV light generation apparatus 1 and the laser apparatus 3 is referred to as an EUV light generation system 11. As shown in FIG. 1 and described in detail below, the EUV light generation apparatus 1 may include a chamber 2 and a target supply unit 26. The chamber 2 may be sealable. The target supply unit 26 may be attached so as to penetrate the wall of the chamber 2, for example. The material of the target substance supplied from the target supply unit 26 may include, but is not limited to, tin, terbium, gadolinium, lithium, xenon, or a combination of any two or more thereof.

  The wall of the chamber 2 may be provided with at least one through hole. A window 21 may be provided in the through hole, and the pulse laser beam 32 output from the laser device 3 may pass through the window 21. In the chamber 2, for example, an EUV collector mirror 23 having a spheroidal reflecting surface may be disposed. The EUV collector mirror 23 may have first and second focal points. On the surface of the EUV collector mirror 23, for example, a multilayer reflective film in which molybdenum and silicon are alternately laminated may be formed. The EUV collector mirror 23 is preferably arranged such that, for example, the first focal point thereof is located in the plasma generation region 25 and the second focal point thereof is located at the intermediate focal point (IF) 292. A through hole 24 may be provided at the center of the EUV collector mirror 23, and the pulse laser beam 33 may pass through the through hole 24.

  The EUV light generation apparatus 1 may include an EUV light generation control apparatus 5, a target sensor 4, and the like. The target sensor 4 may have an imaging function and may be configured to detect the presence, trajectory, position, speed, and the like of the target 27.

  Further, the EUV light generation apparatus 1 may include a connection unit 29 that allows the inside of the chamber 2 and the inside of the exposure apparatus 6 to communicate with each other. A wall 291 in which an aperture 293 is formed may be provided inside the connection portion 29. The wall 291 may be arranged such that its aperture 293 is located at the second focal position of the EUV collector mirror 23.

  Furthermore, the EUV light generation apparatus 1 may include a laser beam traveling direction control unit 34, a laser beam focusing mirror 22, a target recovery unit 28 for recovering the target 27, and the like. The laser beam traveling direction control unit 34 may include an optical element for defining the traveling direction of the laser beam and an actuator for adjusting the position, posture, and the like of the optical element.

2.2 Operation Referring to FIG. 1, the pulsed laser beam 31 output from the laser device 3 passes through the window 21 as the pulsed laser beam 32 through the laser beam traveling direction control unit 34 and enters the chamber 2. May be. The pulse laser beam 32 may travel along the at least one laser beam path into the chamber 2, be reflected by the laser beam collector mirror 22, and irradiate at least one target 27 as the pulse laser beam 33.

  The target supply unit 26 may be configured to output the target 27 toward the plasma generation region 25 inside the chamber 2. The target 27 may be irradiated with at least one pulse included in the pulse laser beam 33. The target 27 irradiated with the pulsed laser light is turned into plasma, and radiation light 251 can be emitted from the plasma. The EUV light 252 included in the radiation light 251 may be selectively reflected by the EUV collector mirror 23. The EUV light 252 reflected by the EUV collector mirror 23 may be condensed at the intermediate condensing point 292 and output to the exposure apparatus 6. A single target 27 may be irradiated with a plurality of pulses included in the pulse laser beam 33.

  The EUV light generation controller 5 may be configured to control the entire EUV light generation system 11. The EUV light generation controller 5 may be configured to process image data of the target 27 imaged by the target sensor 4. Further, the EUV light generation control device 5 may be configured to control the timing at which the target 27 is output, the output direction of the target 27, and the like. Further, the EUV light generation control device 5 may be configured to control, for example, the oscillation timing of the laser device 3, the traveling direction of the pulse laser light 32, the condensing position of the pulse laser light 33, and the like. The various controls described above are merely examples, and other controls may be added as necessary.

3. Explanation of Terms 3.1 Above 2. Terms used in this disclosure are defined as follows.
A “droplet” may be a melted droplet of target material. The shape may be substantially spherical.
The “plasma generation region” may be a three-dimensional space preset as a space where plasma is generated.

3.2 Explanation of Unique Terms for Each Disclosure In the following description, the cross-section or cross-sectional view of each part in the target generation device is the cross-section of the surface including the droplet trajectory output from the nozzle hole, unless otherwise described. Or it may be a sectional view.
The “dense body” may be a crystalline body or a single crystal that is densified by aligning the orientations of the particles constituting the ceramic.
The “stacking direction” may be a direction in which layers are stacked in the stacked body.
“Upstream” and “downstream” of a flow path may correspond to “upstream” and “downstream” in the flow when a fluid flows through the flow path.

4). Target Generation Device Next, an example of a target generation device including the target supply unit 26 shown in FIG. 1 will be described in detail with reference to the drawings.

4.1 Configuration FIG. 2 is a schematic diagram illustrating a schematic configuration example of a target generation device including the target supply unit 26 illustrated in FIG. 1. As shown in FIG. 2, the target generation device may include a pressure regulator 520, a temperature variable device 540, a control unit 51, and a piezo power source 552 in addition to the target supply unit 26.

  The target supply unit 26 may include a tank unit 260, a filter unit 300, a nozzle unit 266, and a piezo element 551.

  The tank unit 260 may include a tank 261 and a lid 262. The target material 271 may be stored in the tank unit 260. The target material 271 may be a metal target such as tin (Sn). A cylindrical protrusion 263 that protrudes into the chamber 2 (see FIG. 1) may be provided at the lower portion of the tank 261. The convex portion 263 may be formed integrally with the tank 261 or may be a separate body.

  The material of the tank 261, the convex part 263, the lid 262, and the filter part 300 may be a material having low reactivity with the target material 271. The material having low reactivity with the target material 271 may be, for example, molybdenum (Mo).

  A filter part 300 that houses the filter laminate 100 may be provided on the bottom surface of the convex part 263. A flow path communicating from the tank 261 to the nozzle portion 266 may be formed inside the convex portion 263 and the filter portion 300. This flow path may be open on the lower surface of the filter unit 300. Details of the filter unit 300 will be described later.

  The nozzle part 266 may be provided so as to cover the opening on the lower surface of the filter part 300. A nozzle hole 267 may be formed in the nozzle portion 266. The nozzle hole 267 may communicate with the flow path in the filter unit 300. The hole diameter of the nozzle hole 267 may be, for example, 2 to 6 μm. The material of the nozzle part 266 may be molybdenum (Mo).

  The pressure regulator 520 may include a pressure controller 525, an exhaust device 524, valves 521 and 522, and a pressure sensor 523. The exhaust device 524 may be connected to an inert gas cylinder 530 via a gas pipe 531. The cylinder 530 may be provided with a valve 534 for adjusting the pressure of the gas to be supplied.

  Valves 521 and 522 may be provided at two locations on the gas pipe 531. A gas pipe 532 may be branched from the gas pipe 531 between the valves 521 and 522. The gas pipe 532 may communicate with the tank unit 260. The pressure sensor 523 may be provided for the gas pipe 532.

  The temperature variable device 540 may include a heater 541, a temperature sensor 542, a heater power supply 543, and a temperature control unit 544.

  The heater 541 may be provided to heat the target material 271 in the tank unit 260. The installation position of the heater 541 may be the outer periphery of the side surface of the tank 261. The temperature sensor 542 may be arranged to measure the temperature of the tank part 260 or the target material 271 in the tank part 260. The installation position of the temperature sensor 542 may be the side surface of the tank 261. The heater power supply 543 may supply a current to the heater 541.

  The output signal line from the control unit 51 may be connected to the piezo power supply 552, the temperature control unit 544, the pressure control unit 525, and the EUV light generation control device 5. An input signal line to the control unit 51 may be connected to the temperature control unit 544, the pressure control unit 525, and the EUV light generation control device 5.

4.2 Operation The control unit 51 of the target generation device illustrated in FIG. 2 may execute the following processing when a droplet output preparation signal is input from the EUV light generation control device or the control unit of the external device.

  That is, the control unit 51 may first control the pressure regulator 520 so that the gas in the tank unit 260 is exhausted. In contrast, the pressure controller 525 of the pressure regulator 520 may drive the exhaust device 524 with the valve 521 closed and the valve 522 opened.

  Subsequently, the control unit 51 may control the temperature variable device 540 so that the target material 271 in the tank unit 260 is melted. On the other hand, the temperature controller 544 of the temperature variable device 540 may drive the heater 541 so that the detected value of the temperature sensor 542 becomes a predetermined temperature Top, for example. For example, when tin (Sn) is used as the target material 271, the predetermined temperature Top may be a temperature equal to or higher than the melting point of tin (temperature 232 ° C.). Further, the predetermined temperature Top may be a temperature range. The temperature range may be, for example, 240 ° C to 290 ° C.

  Subsequently, the control unit 51 determines whether or not the detected value of the temperature sensor 542 is maintained at a predetermined temperature Top or higher for a predetermined time. If the detected value is maintained, the control unit 51 determines whether the EUV light generation controller 5 or the external device You may notify a control part that the output preparation of the droplet was completed.

  Next, when a droplet output signal requesting the output of the droplet 27 is input, the control unit 51 sets the pressure in the tank unit 260 to a predetermined pressure P (for example, 10 MPa (mega It may be ordered to increase the pressure until Pascal)). In response to this command, the pressure controller 525 of the pressure regulator 520 stops the exhaust device 524 and opens the valve 521 while the valve 522 is closed, so that the inert gas from the cylinder 530 enters the tank unit 260. It may be introduced. In addition, when the pressure in the tank unit 260 rises to a predetermined pressure P, the pressure control unit 525 next adjusts the opening and closing of the valves 521 and 522 to change the pressure in the tank unit 260 to the predetermined pressure P. Control to maintain may be executed. The jet of the target material 271 may be output from the nozzle hole 267 in a state where the pressure in the tank unit 260 is maintained at a predetermined pressure P.

  Next, the control unit 51 may control the piezo power supply 552 so that the jet of the target material 271 discharged from the nozzle hole 267 changes to a droplet having a predetermined size and a predetermined cycle. As a result, a desired droplet can be supplied to the plasma generation region 25 (see FIG. 1) in the chamber.

5. Filter Unit Next, the filter unit 300 shown in FIG. 2 will be described in detail with reference to the drawings.

5.1 Configuration FIG. 3 is a cross-sectional view illustrating a schematic configuration example of the filter unit.

  As shown in FIG. 3, the filter unit 300 may include a flange 301, a filter laminate 100, a filter holder 314, and at least one shim 304.

  The material of the flange 301 and the filter holder 314 may be a material having low reactivity with the target material 271. The material having low reactivity with the target material 271 may be, for example, molybdenum (Mo). The material of the shim 304 may also be a material that has low reactivity with the target material 271 (for example, Mo).

  The flange 301 may have a cylindrical shape having the same diameter as the convex portion 263. The flange 301 may be fixed to the convex portion 263 of the tank portion 260 with a bolt (not shown). A gap between the flange 301 and the convex portion 263 may be sealed with an O-ring 304. However, the O-ring 304 is not an essential configuration. That is, when a face seal is formed between the flange 301 and the convex portion 263, the O-ring 304 may be omitted. Alternatively, the gap between the flange 301 and the convex portion 263 may be sealed with both a seal by the O-ring 304 and a face seal.

  In the flange 301, a flow path FL1 continuous with the flow path FL1 in the convex portion 263 may be formed. In the flow path FL <b> 1 in the flange 301, an enlarged diameter part for accommodating the filter laminate 100 may be formed. The filter laminated body 100 may be accommodated in this enlarged diameter portion without backlash using the filter holder 314 and at least one shim 304. Thereby, the filter laminated body 100 may be provided so that the lamination direction may substantially correspond to the extending direction of the flow path FL1 in the flange 301. The filter holder 314 and shim 304 may have a cylindrical or ring shape.

  The contact surface between the flange 301 and the filter holder 314 may be a polished surface. The both surfaces of each shim 304, the contact portion between the convex portion 263 and the shim 304, and the contact portion between the filter holder 314 and the shim 304 may be a polished surface. Contact at each polishing surface may form a face seal.

  The filter laminate 100 may filter out particles such as tin oxide contained in the target material 271. The filter laminate 100 may have a structure in which a plurality of filters are laminated. In the example shown in FIG. 3, the filter laminated body 100 which consists of three filters 101-103 is illustrated.

  The three filters 101 to 103 may have filter pore diameters of 20 μm (micrometer), 10 μm, and 6 μm, for example, sequentially from the tank unit 260 side. Each of the filters 101 to 103 may be a porous material such as a porous glass body having an aluminum oxide / silicon dioxide glass as a skeleton.

5.2 Operation In the operation of the filter unit 300, particles contained in the target material 271 are filtered when the liquid target material 271 flowing into the flow path FL1 from the tank unit 260 passes through the filter laminate 100. Also good. Thereby, particles that cause clogging of the nozzle hole 267 and unstable trajectory of the droplet 27 can be removed from the target material 271 flowing into the nozzle portion 266.

5.3 Problem When a porous material is used as a filter, a part of the filter may be lost due to friction caused by thermal expansion / contraction during assembly or heating / cooling, and particles may be generated. For example, particles generated from the filter 103 may not be removed by the filter laminate 100. Such particles can reach the nozzle hole 267 and cause the nozzle hole 267 to become clogged and the trajectory of the droplet 27 to become unstable. Therefore, in the following embodiment, a filter structure, a target generation device, and a method for manufacturing the filter structure that can suppress the generation of particles due to the filter laminate 100 will be exemplified.

6). Embodiment 1
In the first embodiment, an intermediate member for attaching the filter laminate to the filter holder 314 may be provided. Hereinafter, this intermediate member is referred to as a socket.

6.1 Configuration FIG. 4 is a cross-sectional view illustrating a schematic configuration example of the filter unit according to the first embodiment. In the following description, a configuration different from the configuration of the filter unit 300 illustrated in FIG. 3 will be described.

  As illustrated in FIG. 4, the filter unit 310 according to the first embodiment may have a configuration in which the filter stack 100 is replaced with a filter structure 110 in the same configuration as the filter unit 300 illustrated in FIG. 3. .

  The filter structure 110 may include a filter stack 111 and a socket 115.

  The filter laminate 111 may be a disk-shaped filter having a multilayer structure. This multilayer structure may be a structure formed by a lamination molding process. The number of layers in the multilayer structure may be three. FIG. 3 shows a case of three layers 112 to 114.

  The layers 112 to 114 may be porous materials having different hole diameters. For example, alumina may be used as the porous material.

  The hole diameter of each of the layers 112 to 114 may be larger as the layer is located upstream of the flow of the target material 271 (also referred to as the upstream side in the stacking direction; hereinafter the same). For example, the hole diameter of the layer 112 positioned at the uppermost stream with respect to the flow of the target material 271 may be 12 μm, and in this case, the hole diameter of the layer 113 may be 0.8 μm. Further, the hole diameter of the layer 114 located on the most downstream side with respect to the flow of the target material 271 may be 0.2 μm.

  At least one of the layers 112 to 114 may be thicker than the other layers. For example, layer 112 may be thicker than the other layers 113 and 114. In that case, the layer 112 can act as a support for the other layers 113 and 114 and the entire filter stack 111.

  In addition, the layers 112 to 114 may be thicker as the layers are located upstream with respect to the flow of the target material 271. The thickness of the layer 112 may be 2 mm (millimeter). In this case, the thickness of the layer 113 may be 30 μm, and the thickness of the layer 114 may be 20 μm.

  The socket 115 may hold the filter laminated body 111 and may have a shape that fits in the filter holder 314. At that time, the contact portion between the socket 115 and the filter holder 314 may extend around the side surface of the socket 115 in order to prevent leakage of the target material 271.

  The socket 115 may be an annular member made of a bulk made of the same material as the filter laminate 111. For example, the socket 115 may be a dense body of alumina (alumina ceramic) or a sapphire single crystal.

  In addition, the porosity of each layer 112-114 which comprises the filter laminated body 111 may be 40-50%, for example. On the other hand, the porosity of the socket 115 may be 2% or less, for example.

  The contact portions of the socket 115 and the filter holder 314 may be polished. Thereby, a face seal may be formed between the socket 115 and the filter holder 314.

  The filter laminate 111 and the socket 115 may be integrated by bonding. When alumina is used as the material of the filter laminate 111 and the socket 115, the bonding may be thermal bonding or glass bonding. Moreover, after joining the filter laminated body 111 and the socket 115 with an alumina adhesive agent, you may join both by baking.

6.2 Operation In the above configuration, the filter structure 110 in a state where the filter stack 111 and the socket 115 are joined may be attached to the filter holder 314. Thus, when the filter laminated body 111 is joined to the socket 115 in advance, the socket 115 can be assembled to the filter holder 314. As described above, the socket 115 can be formed of, for example, a dense ceramic or single crystal. Therefore, it is possible to reduce the loss of the porous material constituting the filter laminate 111 due to friction during assembly or heating / cooling. As a result, it is possible to suppress the generation of particles that occur during assembly or heating / cooling, thereby suppressing clogging of the nozzle holes 267 and instability of the droplet trajectory.

7). Modified Example of Embodiment 1 FIGS. 5 and 6 show a modified example of the filter laminate 111 shown in FIG. In the following description, a configuration different from the configuration of the filter laminate 111 shown in FIG. 4 will be described.

7.1 Configuration 7.1.1 First Modification FIG. 5 is a cross-sectional view illustrating a schematic configuration example of a filter laminate according to a first modification. As shown in FIG. 5, the filter laminate 110A may be a multilayer filter having a dome shape. In FIG. 5, the material (material), the hole diameter, the porosity, and the thickness of the layer 112 a located in the uppermost stream with respect to the flow of the target material 271 may be the same as that of the layer 112. Similarly, the material (material), pore diameter, porosity and thickness of the layers 113a and 114a may be the same as those of the layers 113 and 114, respectively.

7.1.2 Second Modification FIG. 6 is a cross-sectional view illustrating a schematic configuration example of a filter laminate according to a second modification. As shown in FIG. 6, the filter laminate 110B may have a configuration in which a cylindrical portion is extended with respect to the dome shape of the filter laminate 110A shown in FIG. This cylindrical portion may be separated from the inner surface of the socket 115. The material (material), pore diameter, porosity and thickness of the layers 112b to 114b may be the same as those of the layers 112 to 114, respectively.

7.1.3 Other Modifications In addition to the above-described modification examples, the filter laminate 111 may be modified into various shapes such as a polygonal pyramid shape.

7.2 Action By using the filter laminate 111 as a dome-shaped or polygonal pyramid-shaped member, the filtration area can be increased. Thereby, the collection amount (or collection rate) of particles contained in the target material 271 can be improved. Moreover, the exchange cycle of a filter laminated body may also become long with expansion of a filtration area.

8). Embodiment 2
In the second embodiment, a hollow cylindrical filter laminate may be used.

8.1 Configuration FIG. 7 is a cross-sectional view illustrating a schematic configuration example of a filter unit according to the second embodiment. FIG. 8 is a perspective view showing a schematic configuration example of the filter structure shown in FIG. FIG. 9 is a view showing a cross-sectional structure when the filter laminate in the filter structure shown in FIG. 8 is cut in a plane perpendicular to the extending direction of the internal space. In the following description, a configuration different from the configuration of the filter unit 310 illustrated in FIG. 4 will be described.

  As illustrated in FIG. 7, the filter unit 320 according to the second embodiment may have a configuration in which the filter structure 110 is replaced with the filter structure 120 in the same configuration as the filter unit 310 illustrated in FIG. 4. .

  As shown in FIG. 8, the filter structure 120 may include a filter laminate 121, a cap 122, and a socket 126.

  As shown in FIG. 9, the filter laminate 121 may be a hollow cylindrical filter having a multilayer structure. The material (material), the hole diameter, the porosity, and the thickness of the layer 123 located on the outermost periphery that is the most upstream position with respect to the flow of the target material 271 may be the same as those of the layer 112. Similarly, the material (material), pore diameter, porosity and thickness of the layers 124 and 125 may be the same as those of the layers 113 and 114, respectively.

  Further, as shown in FIG. 8, the opening at one end in the longitudinal direction of the filter laminate 121 having a hollow cylindrical shape may be sealed with a cap 122. The cap 122 may be a plate-like member configured with a bulk made of the same material as the filter laminate 121. For example, the cap 122 may be a dense body of alumina (alumina ceramic) or a sapphire single crystal.

  The socket 126 may be provided at the other end in the longitudinal direction of the filter laminate 121. The socket 126 may hold the filter laminate 121 and may have a shape that fits in the filter holder 314 without a gap. The material of the socket 126 may be the same as that of the socket 115 in the first embodiment.

  The contact portions of the socket 126 and the filter holder 314 may be polished. Thereby, a face seal may be formed between the socket 126 and the filter holder 314.

  The filter laminate 121 and the cap 122, and the filter laminate 121 and the socket 126 may be integrated by bonding. Each joint may be the same as the joint between the filter laminate 111 and the socket 115 exemplified in the first embodiment.

  As shown in FIG. 7, the filter structure 120 having the above configuration may be assembled to the filter holder 314 such that the cap 122 side protrudes into the flow path FL1 on the tank portion 260 side.

8.2 Action As in the first embodiment, the filter structure 110 in which the filter laminate 111 and the socket 115 are joined can be attached to the filter holder 314. Therefore, the filter structure 110 is generated during assembling, heating, and cooling. Generation of particles can be suppressed. Thereby, clogging of the nozzle hole 267 and instability of the droplet trajectory can be suppressed.

9. Modification of Embodiment 2 The shape of the filter laminate 121 according to Embodiment 2 is not limited to the hollow cylindrical shape. The modification is shown below.

9.1 Configuration 9.1.1 First Modified Example FIG. 10 is a diagram showing a cross-sectional shape of the filter laminate according to the first modified example when the filter laminate is cut in a plane perpendicular to the extending direction of the internal space. It is. As shown in FIG. 10, the filter laminate 121 </ b> A may have a regular hexagonal cross-sectional shape including a flow path of the target material 271 at the center. However, it is not limited to a regular hexagon, and may be various polygonal shapes. Further, the outer contour shape of the outermost peripheral layer 123a and the outer contour shape of the inner peripheral layers 124a and 125a are not necessarily similar. That is, the cross-sectional shape may be different for each of the layers 123 to 125. The materials (materials), pore diameter, porosity, and thickness of the layers 123a to 125a may be the same as those of the layers 112 to 114, respectively.

9.1.2 Second Modified Example FIG. 11 is a diagram showing a cross-sectional shape when the filter laminate according to the second modified example is cut in a plane perpendicular to the extending direction of the internal space. As shown in FIG. 11, the filter laminate 121B may have a sawtooth shape in which the outer contour shape of the outermost peripheral layer 123b repeats unevenness. In the center, a flow path of the target material 271 may be provided. The outer contour shape of the outermost peripheral layer 123a and the outer contour shapes of the inner peripheral layers 124a and 125a are not necessarily similar. Further, the material (material), pore diameter, porosity and thickness of the layers 123b to 125b may be the same as those of the layers 112 to 114, respectively.

9.2 Action As described above, the amount of collected particles (collection rate) can be reduced by changing the cross-sectional shape so that the circumference of the outer contour in the cross-sectional shape when the filter laminate is cut into pieces is increased. It may be possible to improve further. In addition, the cross-sectional shape of a filter laminated body may be suitably changed with the manufacturing method. For example, the polygonal filter laminate 121A exemplified with reference to FIG. 10 can be manufactured by combining a plurality of plate-like members. In addition, the shape of the cap that seals the opening at one end of the filter laminate may be appropriately changed according to the cross-sectional shape of the filter laminate.

10. Embodiment 3
In the configuration of the second embodiment, the hollow cylindrical filter laminate may protrude not on the tank portion 260 side but on the nozzle portion 266 side.

10.1 Configuration FIG. 12 is a cross-sectional view illustrating a schematic configuration example of a filter unit according to the third embodiment. FIG. 13 is a view showing a cross-sectional structure when the filter laminate in the filter section shown in FIG. 12 is cut in a plane perpendicular to the extending direction of the internal space. In the following description, a configuration different from the configuration of the filter unit 320 illustrated in FIG. 7 will be described.

  As illustrated in FIG. 12, the filter unit 330 according to the third embodiment may have a configuration in which the filter structure 120 is replaced with the filter structure 130 in the same configuration as the filter unit 310 illustrated in FIG. 7. . The filter structure 130 may have a configuration in which the filter structure 120 is turned upside down in a portion other than the filter stacked body 131.

  As shown in FIG. 13, the filter laminate 131 may be a hollow cylindrical filter having a multilayer structure, like the filter laminate 121. However, since the positional relationship between the upstream side and the downstream side with respect to the flow of the target material 271 is reversed, the layer 133 located on the innermost periphery among the layers 133 to 135 constituting the filter laminate 131 is located on the uppermost stream, The layer 135 located on the outermost periphery may be located on the most downstream side. The material (material), pore diameter, porosity and thickness of each layer 133 to 135 may be the same as those of the layers 112 to 114, respectively.

10.2 Action According to the configuration according to the third embodiment, the same effect can be obtained by the same action as in the second embodiment.

11. Embodiment 4
In the above-described embodiment, the filter holder and the socket may be integrated. In the following description, a configuration different from this configuration will be described based on the filter unit 320 shown in FIG. However, the integration of the filter holder and the socket exemplified in the fourth embodiment may be applicable to other embodiments.

11.1 Configuration FIG. 14 is a cross-sectional view illustrating a schematic configuration example of a filter unit according to the fourth embodiment. As shown in FIG. 14, in the filter unit 340 according to the fourth embodiment, the filter holder 314 and the socket 126 shown in FIG. 7 are replaced with an integrated socket 144.

  The socket 144 may hold the filter laminate 121 and may have a shape that fits within the flange 301. At that time, the contact portion between the socket 144 and the flange 301 may extend around the side surface of the socket 144 in order to prevent leakage of the target material 271.

  The socket 144 may be an annular member made of a bulk made of the same material as the filter laminate 121. For example, the socket 144 may be a dense body of alumina (alumina ceramic) or a sapphire single crystal.

  The contact portions of the socket 144 and the flange 301 may be polished. Thereby, a face seal may be formed between the socket 144 and the flange 301.

  The filter laminate 121 and the socket 144 may be integrated by bonding. When alumina is used for the filter laminate 121 and alumina or sapphire single crystal is used for the material of the socket 144, these bondings may be thermal bonding or glass bonding. Moreover, after joining the filter laminated body 121 and the socket 144 with an alumina adhesive agent, you may join both by baking.

  The socket 144 may have a groove for receiving the shim 304. Each of the contact surfaces of the flange 301 and the socket 144 may be a polished surface. Further, the contact portion between the socket 144 and the shim 304 may be a polished surface. Contact at each polishing surface may form a face seal. However, when a face seal is formed between the socket 144 and the convex portion 263, the shim 304 may be omitted.

11.2 Action According to the fourth embodiment, in addition to the effects of the above-described embodiments, it is possible to replace a component including the filter holder and the socket with one socket. Thereby, the configuration of the filter structure can be simplified. As a result, the manufacturing cost of the filter structure can be reduced.

12 Embodiment 5
In the embodiment described above, the socket may be formed by thermal spraying. In the following description, an example in which the filter holder 314 and the socket 115 are integrated in the filter unit 310 shown in FIG. 4 as a base, and the socket is formed by thermal spraying in this configuration will be exemplified. However, the formation by thermal spraying of the socket illustrated in the fifth embodiment may be applicable to other embodiments.

12.1 Configuration FIG. 15 is a cross-sectional view illustrating a schematic configuration example of a filter unit according to the fifth embodiment. As shown in FIG. 15, the filter unit 350 according to the fifth embodiment has a configuration in which the filter structure 110 and the filter holder 314 are replaced with the filter structure 150 in the same configuration as the filter unit 310 shown in FIG. May be.

  That is, the filter holder 314 and the socket 115 may be replaced with an integrated socket 156. Further, the filter laminate 111 may be replaced with the filter laminate 151.

  The filter laminate 151 may have a structure in which the first filter 152 to the third filter 154 that are different disk-shaped members are stacked. The shape, material (material), pore diameter, porosity, and thickness of each of the filters 152 to 154 may be the same as those of the layers 112 to 114, respectively. However, instead of the filter laminate 151, other filter laminates such as the filter laminate 100 may be used.

  The socket 156 may be a member formed by thermal spraying on the filter laminate 151. By forming the socket 156 by thermal spraying, it is possible to manufacture the filter structure 150 while integrally holding the plurality of filters 152 to 154. In addition, the manufacturing process of the filter structure 150 by thermal spraying is mentioned later.

  The socket 156 may hold the filter laminate 151 and have a shape that fits in the flange 301. At that time, the contact portion between the socket 156 and the flange 301 may extend around the side surface of the socket 156 in order to prevent leakage of the target material 271.

  The material of the socket 156 may be a material (for example, Mo) having low reactivity with the target material 271, similarly to the flange 301.

  The contact portions of the socket 156 and the flange 301 may be polished. Thereby, a face seal may be formed between the socket 156 and the flange 301. Moreover, the contact part of the socket 156 and the convex part 263 may each be grind | polished. Thereby, a face seal may be formed between the socket 156 and the convex portion 263. In that case, the shim 304 between the socket 156 and the convex portion 263 can be omitted.

12.2 Action When the socket 156 and the filter laminate 151 are integrated by forming the socket 156 by thermal spraying, the material (material) of the filter laminate 151 is selected when the material (material) of the socket 156 is selected. There is no need to consider it. Therefore, the same material as the material of the flange 301 can be selected as the material of the socket 156. By making the material (material) of the socket 156 and the material (material) of the flange 301 the same, it is possible to reduce stress caused by a difference in thermal expansion during assembly or heating / cooling. As a result, it is possible to suppress the generation of particles that occur during assembly or heating / cooling, thereby suppressing clogging of the nozzle holes 267 and instability of the droplet trajectory.

13. Embodiment 6
In the above-described embodiment, the filter laminate may include a support plate for increasing rigidity. In the following description, a configuration different from this configuration will be described based on the filter unit 350 shown in FIG. However, the support plate illustrated in the sixth embodiment may be applicable to other embodiments.

13.1 Configuration FIG. 16 is a cross-sectional view illustrating a schematic configuration example of a filter unit according to the sixth embodiment. As illustrated in FIG. 16, in the filter unit 360 according to the sixth embodiment, the socket 156 may further hold the support plate 165 in the filter unit 350 illustrated in FIG. 15.

  The support plate 165 may be a disk-shaped plate member having the same diameter as the first filter 152 to the third filter 154, for example. The material of the support plate 165 may be a material having low reactivity with the target material 271 (for example, Mo), glass, or the like.

  A plurality of through holes may be formed in the center of the support plate 165. The number of through holes may be, for example, 10 to 100. Moreover, the hole diameter of each through-hole may be about 100-1500 micrometers, for example.

13.2 Action By supporting the filter laminate 151 with the support plate 165, the rigidity of the filter structure 160 can be increased. Thereby, for example, even when a relatively high pressure is applied to the target material 271 in the tank portion 260, it is possible to suppress damage to the filter laminate 151.

14 Constituent material In the above-described embodiment, alumina (or alumina ceramic) or sapphire single crystal is exemplified as the material of the filter laminate, the socket, and the cap. Here, other materials are exemplified.

14.1 Socket Cap Material It is desirable that the material of the socket and cap satisfy the following conditions 1 and 2.
(1) The material has low reactivity with the melted target material 271 (for example, tin). (2) The difference in thermal expansion coefficient with the flange 301 is small.

Some examples of materials satisfying condition 1 are shown in Table 1 below.

  Further, as described above, the metal material used as the material of the flange 301 may be molybdenum (Mo) having low reactivity with the target material (for example, tin). Therefore, as the material of the socket, a material having a small difference in thermal expansion coefficient from molybdenum may be selected from, for example, Table 1 above. The difference in thermal expansion coefficient from molybdenum may be small, for example, within a range of ± 20% with respect to the thermal expansion coefficient of molybdenum. As such materials, silicon carbide, tungsten carbide, aluminum nitride, zirconium boride, and boron carbide are listed in Table 1 above.

14.2 Filter material The material of the filter laminate may be the same material with a different structure from the material used for the socket, but may also be a different material. The material of the filter laminate is preferably a material that satisfies the following conditions 3 and 4 in addition to the above conditions 1 and 2 for the socket and cap materials.
(3) A material capable of forming a porous structure (4) A material that can be joined to a material used for a socket or a cap

  As a material of the filter laminate, a material that satisfies the above conditions 1 to 4 may be selected from Table 1, or another material that satisfies the conditions 1 to 4 and has similar characteristics may be selected.

15. Manufacturing process of filter structure by thermal spraying Next, the manufacturing process of the filter structure by thermal spraying exemplified in Embodiment 5 or 6 will be described in detail with reference to the drawings. However, in the following description, the manufacturing process of the filter structure 160 exemplified in the sixth embodiment will be exemplified.

  FIG. 17 is a flowchart showing an example of the manufacturing process of the filter structure by thermal spraying. 18 to 23 are cross-sectional views of the filter structure 160 in the main process for explaining the manufacturing process shown in FIG.

  As shown in FIG. 17, in the manufacturing process of the filter structure 160, the support plate 165 having the masking material 1006, the third filter 154, the second filter 153, and the first filter 152 having the masking material 1003 are bonded to the adhesive. (Step S101). In that case, as shown in FIG. 18, you may use the 3rd jig 1007 as a support body. In addition, a cyanoacrylate adhesive may be used as the adhesive. However, other adhesives may be used as long as they can be removed with a solvent or the like. Thereby, the filter assembly 161 (refer FIG. 18) by which the support plate 165 was adhere | attached on the filter laminated body 151 which consists of the 1st filter 152-the 3rd filter 154 may be created. The filter assembly 161 may include masking materials 1003 and 1006.

  Next, as shown in FIG. 19, a spray material 1008 may be formed by spraying a socket material on the entire outside of the filter assembly 161 (step S102). The socket material may be molybdenum. Further, the thickness of the thermally sprayed socket material may be about 500 μm at the thickest portion.

  Next, as shown in FIG. 20, the outer periphery of the sprayed portion 1008 may be mechanically processed (step S103). The outer diameter of the sprayed portion 1009 after processing may be the same as the outer diameter of the same member in the completed filter structure 160.

  Next, as shown in FIG. 21, a ring member 1010 for locking the filter structure 160 to the flange 301 may be welded to the sprayed portion 1009 (step S104).

  Next, as shown in FIG. 22, the outer shape of the holding unit 1009 may be mechanically processed (step S105). Thereby, the masking materials 1003 and 1006 in the filter assembly 161 may be exposed, respectively.

  Next, you may grind | polish the contact scheduled part with the flange 301 and the convex part 263 in the welded ring member 1010 (step S106).

  Next, as shown in FIG. 23, the exposed masking materials 1003 and 1006 may be removed with a solvent (step S107). Thereby, the structure of the filter structure 160 may be obtained. Next, the adhesive may be removed with a solvent (step S108).

  Next, the filter structure 160 may be washed with pure water or the like (step S109), and particles remaining in the washed filter structure 160 may be measured (step S110). The cleaning of the filter structure 160 may be repeatedly performed (step S111; NO) until the measured amount of particles falls within a predetermined allowable range (step S111; YES).

  The above description is intended to be illustrative only and not limiting. Thus, it will be apparent to one skilled in the art that modifications may be made to the embodiments of the present disclosure without departing from the scope of the appended claims.

  Terms used throughout this specification and the appended claims should be construed as "non-limiting" terms. For example, the terms “include” or “included” should be interpreted as “not limited to those described as included”. The term “comprising” should be interpreted as “not limited to what is described as having”. Also, the indefinite article “a” or “an” in the specification and the appended claims should be interpreted to mean “at least one” or “one or more”.

  26 ... target supply unit, 27 ... droplet, 110, 110A, 110B, 120, 130, 150, 160 ... filter structure, 111, 121, 121A, 121B, 131, 151 ... filter laminate, 112, 112a, 112b , 113, 113a, 113b, 114, 114a, 114b, 123, 123a, 123b, 124, 124a, 124b, 125, 125a, 125b, 133, 134, 135 ... layer, 115, 126, 144, 154 ... socket, 122 ... Cap, 152,153,154 ... Filter, 165 ... Support plate, 260 ... Tank, 261 ... Tank, 262 ... Lid, 263 ... Convex, 266 ... Nozzle, 267 ... Nozzle hole, 271 ... Target material, 301 ... Flange, 304 ... Shim, 310, 32 , 330,340,350,360 ... filter unit, 314 ... filter holder

Claims (12)

A filter structure including a filter made of a porous material and a socket integrated with the filter by bonding;
A flange containing the filter structure and having a flow path passing through the filter structure therein;
A tank portion in which there is a space communicating with the flow path in the flange and storing a predetermined target material;
A nozzle part provided on the flange and communicating with the space in the tank part via the flow path in the flange;
With
The porosity of the filter is greater than the porosity of the socket,
The filter and the socket are integrated by thermal bonding,
Data Getto generating device. A filter structure including a filter made of a porous material and a socket integrated with the filter by bonding;
A flange containing the filter structure and having a flow path passing through the filter structure therein;
A tank portion in which there is a space communicating with the flow path in the flange and storing a predetermined target material;
A nozzle part provided on the flange and communicating with the space in the tank part via the flow path in the flange;
With
The porosity of the filter is greater than the porosity of the socket,
The filter and the socket are integrated by glass bonding,
Data Getto generating device. A filter structure including a filter made of a porous material and a socket integrated with the filter by bonding;
A flange containing the filter structure and having a flow path passing through the filter structure therein;
A tank portion in which there is a space communicating with the flow path in the flange and storing a predetermined target material;
A nozzle part provided on the flange and communicating with the space in the tank part via the flow path in the flange;
With
The porosity of the filter is greater than the porosity of the socket,
The socket is integrated by being sprayed on the filter,
Data Getto generating device. A filter structure including a filter made of a porous material and a socket integrated with the filter by bonding;
A flange containing the filter structure and having a flow path passing through the filter structure therein;
A tank portion in which there is a space communicating with the flow path in the flange and storing a predetermined target material;
A nozzle part provided on the flange and communicating with the space in the tank part via the flow path in the flange;
With
The porosity of the filter is greater than the porosity of the socket,
The filter and the socket are made of a material having substantially the same thermal expansion coefficient.
Data Getto generating device. A filter structure including a filter made of a porous material and a socket integrated with the filter by bonding;
A flange containing the filter structure and having a flow path passing through the filter structure therein;
A tank portion in which there is a space communicating with the flow path in the flange and storing a predetermined target material;
A nozzle part provided on the flange and communicating with the space in the tank part via the flow path in the flange;
With
The porosity of the filter is greater than the porosity of the socket,
The filter and the socket are made of the same material,
Data Getto generating device. A filter structure including a filter made of a porous material and a socket integrated with the filter by bonding;
A flange containing the filter structure and having a flow path passing through the filter structure therein;
A tank portion in which there is a space communicating with the flow path in the flange and storing a predetermined target material;
A nozzle part provided on the flange and communicating with the space in the tank part via the flow path in the flange;
With
The porosity of the filter is greater than the porosity of the socket,
The filter is made of alumina;
The socket is made of a dense body of alumina or a single crystal of sapphire,
Data Getto generating device. A filter structure including a filter made of a porous material and a socket integrated with the filter by bonding;
A flange containing the filter structure and having a flow path passing through the filter structure therein;
A tank portion in which there is a space communicating with the flow path in the flange and storing a predetermined target material;
A nozzle part provided on the flange and communicating with the space in the tank part via the flow path in the flange;
With
The porosity of the filter is greater than the porosity of the socket,
The socket is formed of a material containing at least one of molybdenum and tungsten;
The filter is composed of a porous glass body having an aluminum oxide / silicon dioxide glass as a skeleton,
Data Getto generating device. A filter structure including a filter made of a porous material and a socket integrated with the filter by bonding;
A flange containing the filter structure and having a flow path passing through the filter structure therein;
A tank portion in which there is a space communicating with the flow path in the flange and storing a predetermined target material;
A nozzle part provided on the flange and communicating with the space in the tank part via the flow path in the flange;
With
The porosity of the filter is greater than the porosity of the socket,
The filter has a dome shape;
Data Getto generating device. A filter structure including a filter made of a porous material and a socket integrated with the filter by bonding;
A flange containing the filter structure and having a flow path passing through the filter structure therein;
A tank portion in which there is a space communicating with the flow path in the flange and storing a predetermined target material;
A nozzle part provided on the flange and communicating with the space in the tank part via the flow path in the flange;
With
The porosity of the filter is greater than the porosity of the socket,
The filter has a hollow shape that opens at both ends in the longitudinal direction,
A cap for sealing the opening at one end in the longitudinal direction;
The socket is provided at the other end in the longitudinal direction,
Data Getto generating device. The target generation device according to claim 9 , wherein a cross-sectional shape of the filter in a direction perpendicular to the longitudinal direction is a circular shape. The target generation device according to claim 9 , wherein a cross-sectional shape of the filter in a direction perpendicular to the longitudinal direction is a polygonal shape or a sawtooth shape. A method of manufacturing a filter structure including a filter made of a porous material and used in a target generation device,
A step of stacking and arranging the filter in which a masking material is partially formed;
Spraying a material having a thermal expansion coefficient substantially equal to that of the filter around the filter on which the masking material is formed;
Processing the material to expose a portion of the masking material;
Removing the masking material;
Manufacturing method.

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